Peek Street Facility Case 

Reviews

Douglas Farver, CHP, SC&A, Inc.

Advisory Board on Radiation and Worker Health, 

Subcommittee for Procedure Reviews

November 16, 2023
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Background Information

 January 29, 2019: SC&A submitted its review of the Peek Street Facility 

(PSF) dose reconstruction (DR) template 

– Review identified eight findings and three observations

 September 29, 2022, Subcommittee on Procedure Reviews (SPR) 

meeting: 

– PSF findings and observations were discussed

– Status of five findings and two observations was placed in abeyance awaiting a 

revision to the PSF DR template

 SC&A tasked to review two PSF DR cases for purpose of addressing the 

remaining three findings and one observation

 October 10, 2023: SC&A submitted its review of the two PSF DR cases

– Review identified four findings
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Review limited to findings 1, 3–4, and 

observation 2 from 2019 PSF review

 2019 finding 1: The assumption of 100% 30–250 keV for the penetrating 

photon energy distribution is unsupported and inconsistent with 

assumptions used in the Hanford technical basis document (TBD).

 2019 finding 3: SC&A was unable to verify the neutron-to-photon ratio 

(N:P) of 1.2 using the cited references.

 2019 finding 4: The dosimeter limit of detection (LOD) used in the DR 

template is not specified in the template, and the LOD value of 0.050 rem 

assumed for photon missed dose based on NIOSH’s calculation is not 

consistent with the Hanford dosimeter information.

 2019 observation 2: The natural uranium physically significant level 

(PSL) in the DR template is not consistent with information in “Excerpts 

from KAPL Radiological History Report” and is not referenced.
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Case 1

 DR completed in 2011

 Energy employee (EE) worked Peek Street Facility (PSF) and 

two other facilities for many years

 EE was diagnosed with two qualifying cancers after 

employment termination

 EE was monitored for photons and electrons and bioassayed 

for natural and enriched uranium
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Case 1 photon energy

 Computer-assisted telephone interview indicates the EE worked with uranium. Based on 

work history and bioassay data, it appears EE worked primarily with uranium material. 

 Table 6-7 of ORAUT-TKBS-0006-6, rev. 04, recommends a photon energy distribution of 

100 % 30–250 keV photons for fuel fabrication facilities at Hanford. 

 NIOSH applied an uncertainty factor of 1.3 to the photon doses and references ORAUTTKBS-0006-6, rev. 04. Table 6-25 of ORAUT-TKBS-0006-6 lists the systematic 

uncertainty for the two-element film dosimeter as 1.2.

 While the DR references the ORAUT-TKBS-0006-6, rev. 04, uncertainty value, neither 

the DR text nor the tool used to calculate the external doses, PSF Calc Wrkbk 1.00 F 

(prototype), was updated to contain the correct uncertainly value (finding 2 in SC&A’s 

PSF DR template review).
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Case 1 neutron dose

 To determine an appropriate neutron-to-photon ratio, NIOSH reviewed TBDs for other 

reactor and critical assembly sites: Hanford, Savannah River Site, Oak Ridge National 

Laboratory, Idaho National Laboratory, Los Alamos National Laboratory, Argonne 

National Laboratory East, Brookhaven National Laboratory, Energy Technology 

Engineering Center. 

 Based on the information provided in these TBDs, NIOSH determined a N:P value of 

1.2:1 is likely claimant favorable for facilities with critical assemblies and small-scale 

research reactors.

 The PSF Calc Wrkbk 1.00 F contains a N:P value of 1.2. A note attached to the N:P 

value cell reads “Based on ratios for research reactors and graphic piles at LANL and X10.”

 SC&A agrees with using a N:P value of 1.2 but believes the basis should be provided in 

the DR or a technical document (finding 3 of SC&A’s DR template review).
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Case 1 missed photon dose findings

 Finding 1: NIOSH did not use the actual number of dosimeter cycles to 

calculate missed photon dose for one cancer for 1 year.

– EE’s dosimeter records indicate 81 dosimeter cycles where both the penetrating and nonpenetrating results were zero or less than half the non-penetrating LOD. 

– NIOSH calculated missed photon dose based on 52 dosimeter cycles. 

 Finding 2: NIOSH did not use the correct nonpenetrating LOD listed in 

attachment C of ORAUT-TKBS-0006-6, rev. 04, to calculate the missed doses to 

one cancer.

– Table 6-13 of ORAUT-TKBS-0006-6, rev. 04 (2010), lists the LOD of the two-element film 

dosimeter as 0.040 rem. It does not specify if the LOD is for penetrating or nonpenetrating 

photons. 

– Attachment C of ORAUT-TKBS-0006-6 gives for 1944–1971: 50 mrem for nonpenetrating, 

40 mrem for penetrating.
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Case 1 enriched uranium intake

 EE submitted one urine bioassay that was analyzed for natural 

uranium and seven urine bioassays that were analyzed for 

enriched uranium.

 EE was not monitored with urine bioassay at PSF but did 

submit several urine bioassays while employed at a related 

site.
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Case 1 enriched uranium intake finding

 Finding 3: NIOSH used the enriched uranium PSL instead of 

the natural uranium PSL for the bioassay.

– EE’s DOE records shows the result and the PSL for each sample in 

units of mass. 

– Page 120, figure 5-23, of “Excerpts from KAPL Radiological History 

Report” show units of μg/day.

– NIOSH’s calculations show the PSL was not converted from units of 

mass to units of activity before being entered in IMBA. 
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Case 2

 DR completed in 2013

 EE worked at PSF and one other facility for many years

 EE diagnosed with qualifying cancer after employment 

termination 

 EE monitored for photons and electrons at PSF, was not 

bioassayed at PSF

 EE monitored for photon and electron and bioassayed for 

natural enriched uranium, plutonium, and fission products at 

the other facility
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Case 2 photon energy

 Because EE was monitored for plutonium via urine bioassay, 100% of the nonpenetrating 

doses were assumed to be attributed to <30 keV photons, in accordance with ORAUT-OTIB0017. In addition, 100% of the penetrating doses were assumed to be attributed to 30–250 

keV photons.

 EE was not bioassayed at PSF. SC&A found no information on the EE’s work location or 

whether the EE would have been exposed primarily to uranium or plutonium. 

 Table 6-7 of ORAUT-TKBS-0006-6, rev. 04, gives the photon energy distribution for fuel 

fabrication facilities as 100% 30–250 keV photons and for radiochemical processing facilities 

as 25% 30–250 keV and 75% >250 keV photons.

 SC&A calculated the EE’s recorded photon doses using both photon energy distributions. 

The 100% 30–250 keV photon energy distribution produced the most claimant-favorable 

probability of causation.

 NIOSH applied an uncertainty factor of 1.3 instead of 1.2 per TBD.
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Case 2 neutron dose

 NIOSH reviewed the TBDs of other reactor and critical assembly sites to 

determine an appropriate N:P: Hanford, Savannah River Site, Oak Ridge 

National Laboratory, Idaho National Laboratory, Los Alamos National 

Laboratory, Argonne National Laboratory East, Brookhaven National 

Laboratory, and the Energy Technology Engineering Center. 

 Based on the information gathered in the reviewed TBDs, NIOSH 

determined an N:P of 1.2:1 is likely claimant favorable for facilities with 

critical assemblies and small-scale research reactors.

 PSF Calc Wrkbk 1.00 F contains an N:P of 1.2. A note attached to the N:P 

cell reads “Based on ratios for research reactors and graphic piles at 

LANL and X-10.”

 SC&A believes the basis should be provided in the DR or a technical 

document, as stated in finding 3 of our DR template review.
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Case 2 missed photon and shallow dose

 EE was assigned missed photon dose at PSF and missed 

neutron dose at another facility. 

 Although not stated in the DR, NIOSH used a dosimeter LOD 

of 0.040 rem, which is consistent with the LOD values for the 

Hanford two-element film dosimeter as shown in table 6-13 of 

ORAUT-TKBS-0006-6.

 NIOSH counted 73 dosimeter cycles for penetrating dose and 

1 dosimeter cycle for nonpenetrating dose.
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Case 2 fission product intake

 EE not monitored for fission products at PSF. 

 EE submitted urine bioassays that were analyzed for fission 

products.

 DOE records show the EE’s bioassay results and the PSL for 

each measurement. All the EE’s fission product bioassay 

results were less than the PSL of 50 dpm/24 hours.

 This is the same value given in figure 23, page 120, of 

“Excerpts from KAPL Radiological History Report.” 

 SC&A concludes that NIOSH used the fission product PSL 

consistent with PSF historical documentation.
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Case 2 plutonium intake

 EE not monitored for plutonium at PSF. 

 EE submitted urine bioassays that were analyzed for 

plutonium.

 DOE records show the EE’s bioassay results and the PSL for 

each measurement. All the EE’s plutonium bioassay results 

were less than the PSL of 0.33 dpm/24 hours.

 This is the same value given in figure 23, page 120, of 

“Excerpts from KAPL Radiological History Report.” 

 SC&A concludes that NIOSH used the plutonium PSL 

consistent with PSF historical documentation.
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Case 2 enriched uranium intake

 EE not monitored for uranium at PSF. 

 EE submitted three urine bioassay that were analyzed for enriched 

uranium.

 EE’s first enriched uranium result and PSL are given as 

0.04 dpm/liter and 5 dpm/liter, respectively. 

 EE’s second and third enriched uranium results are both 

0.02 dpm/24 hours with a PSL of 5 dpm/24 hours. 

 Figure 23 of “Excerpts from KAPL Radiological History Report” 

shows 5 dpm/24 hours as the PSL for enriched uranium. This has 

no impact on the case since NIOSH used a hypothetical sample 

result on the EE’s last day of employment.
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Case 2 enriched uranium intake finding

 Finding 4: NIOSH did not enter one-half the enriched uranium 

PSL into IMBA as stated in the DR. 

– The value NIOSH entered in IMBA is 5 dpm/day, which equals the 

enriched uranium PSL and not the PSL/2. 

– This results in an overestimate of the enriched uranium intake.
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Conclusions

 Since both cases contained 

external and internal monitoring 

data, SC&A was able to review: 

– the applicability and basis of 

assuming a photon energy 

distribution of 100% 30–250 keV 

photons

– the basis of using a neutron-to- photon ratio of 1.2 

– the photon LOD used in the 

recorded and missed dose 

calculations

– how the PSLs are used in the 

internal dose calculations

 Both cases assumed a photon 

energy distribution of 100% 

30–250 keV photons. 

 Both cases assumed a 

neutron-to-photon ratio of 1.2 

and contain the same wording 

as the PSF DR template. 

 Both cases use a penetrating 

photon film dosimeter LOD of 

0.040 rem as listed in 

table 6-13 of the ORAUT- TKBS-0006-6, rev. 04.
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Concerns

 Finding 1: NIOSH did not use 

the actual number of dosimeter 

cycles to calculate missed 

photon dose for one cancer in 

Case 1.

 Finding 2: NIOSH did not use 

the correct nonpenetrating LOD 

listed in attachment C of 

ORAUT-TKBS-0006-6, rev. 04, 

to calculate the missed photon 

doses in Case 1.

 Finding 3: NIOSH used the 

enriched uranium PSL instead 

of the natural uranium PSL for 

Case 1 bioassay.

 Finding 4: NIOSH did not enter 

one-half the enriched uranium 

PSL in IMBA as stated in the 

DR for Case 2.
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Questions?